It is well known that a computer monitor can not display pictures shown on television by directly receiving the signals of television. A technology converting a VGA signals to TV signals and using television as a monitor (TV monitor) has a big drawback that, the resolution of the TV CRT is not high enough to show the text mode or a quality picture as a regular monitor. Although the present multimedia technology, to certain extent, has built up a bridge of mutual communications between the monitor and television, for instance, by plugging television card, sound card or video card, etc. into the extension slot of the computer in order to enable the computer monitor to receive television signals and to display television picture. Alternatively, although the conventional television is merely able to display the audio frequency and the video frequency output by computer, the displaying signals, once being processed by that way, are supposed to decline in such a way as to have a bad influence on the resolution of the picture. In addition, to plug in a television card to a conventional computer may cause a lot of compatibility's problems. In other words, the conventional plug and play computer monitor itself does not has the ability of receiving television signals and displaying television pictures.
Furthermore, the technical means mentioned above are not too well convenient in using in most occasions, such as that of the interactive mutual-act data network which is composed by the computers, broadcast televisions and telecommunications. Therefore, there arises a significant need to develop a multi-functional monitor, such as an interactive multimedia monitor that can characterize an independent and compatible feature in receiving and displaying the computer, television and even radio signals.